1 Human development is the scientific study of processes of change and stability.  The scientific study of human development began with studies of childhood during the nineteenth century.
verb (used with object), cultivated, cultivating. 1. to prepare and work on (land) in order to raise crops; till. 2. to use a cultivator on. 3. to promote or improve the growth of (a plant, crop, etc.) by labor and attention.
A cultivator is any of several types of farm implement used for secondary tillage. One sense of the name refers to frames with teeth (also called shanks) that pierce the soil as they are dragged through it linearly. Another sense refers to machines that use rotary motion of disks or teeth to accomplish a similar result.mall tilling equipment, used in small gardens such as household gardens and small commercial gardens, can provide both primary and secondary tillage. For example, a rotary tiller does both the plowing and the harrowing, preparing a smooth, loose seedbed.